These are the notes of a talk in which we translate from the A1-homotopy theoretic
context an argument from [Mor99] showing that a homotopy invariant presheaf
of spectra on the category of smooth schemes that satisfies Nisnevich descent automatically
satisfies descent for abstract blow-ups.
More concretely, Theorem 3.3.1 in [Mor99] roughly says that a Nisnevich distinguished
square of schemes is homotopy cartesian when seen in the stable A1-homotopy
category. We complete the details of the proof of this theorem and write it in the language
of presheaves of spectra. This is theorem 3.7 in this notes.

Materia(s):

Àrees temàtiques de la UPC::Matemàtiques i estadísticaHomotopia, Teoria de l'